As American forces blasted mountain hideouts in the Tora Bora region of eastern Afghanistan in December 2001, hundreds of Al Qaeda soldiers hastily fled, crossing over unguarded mountain trails and seemingly disappearing into thin air. FRONTLINE asked longtime producer Martin Smith to see what he could find out about these Al Qaeda fighters: where they were hiding, who offered them sanctuary, and whether they were regrouping to plan more attacks.

On Aug. 12, Smith, his co-producer Marcela Gaviria, and cameraman Scott Anger set out on a two-month journey that took them from London to the Gulf of Oman, into the border regions and teeming cities of Pakistan and finally to Saudi Arabia -- bin Laden's homeland -- and Yemen. The documentary "In Search of Al Qaeda" is the story of this journey.

Follow the reporters' progress by clicking on an area name on the map -- starting with London -- to explore more detailed maps of the regions they visited, read their e-mail dispatches from the field, see slideshows of photographs they took along the way, and watch video excerpts from the documentary.

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